A lot of you have complimented Hugh on the wall system used for display. You have excellent taste.
The Cado System was designed by Danish interior architect Poul Cadovius in the 1960s and is a modular series of cabinets and shelves that are mounted using a simple dowel system. It's really pretty ingenius in its simplicity and flexibility. This particular set consists of Brazilian rosewood cabinets and teak shelves, and came from the boardroom at the Detroit Institute of Arts.
The boardroom was in the Gunnar Birkerts-designed northern wing of the museum (circa 1970), which was easy to dislike until the Michael Graves renovation was completed and you realized how great it really was. An entirely new boardroom design was called for (it's dismally beige, by the way), and through the miracle of connections these pieces ended up in appreciative hands.
The original wall panels for the system were teak, but were thrown away in the demolition. It's sad, but I guess if they knew what they had the system would never have ended up in Hugh for your enjoyment!